-er -ey bbb bbe bbo bbr bbx bby be- beb bee beo ber bex bey bob boe boo bor box boy brb bre bro brr brx bry bxb bxo bxx by- bye byo byr ebb ebe ebo ebr ebx eby eeb eee eeo eer eex eey eo- eob eoe eoo eor erb ere ero err ery ex- exe exo exr exx exy eye eyo eyr ob- obb obe obo obr obx oby oeb oee oeo oer oex oey oo- oob ooo oor oox or- orb ore oro orr orx ory ox- oxb oxo oxx oxy oye oyo rbb rbe rbo rbr rbx re- reb ree reo rer rex rey rob roe roo ror rox roy rrb rrr rxr ry- rye ryo ryr ryy xbe xbr xbx xee xer xex xoo xor xox xrx xry xxo xxx xxy xyr xyy ybe ybr yby yeb yee yeo yer yex yey yob yoe yoo yor yox yoy yre yro yxe yxy yyb yye yyy